Preheat oven to 400°F. Line a large, rimmed baking sheet with heavy foil. Lay bacon strips on pan without overlapping. Bake for 10 minutes or until bacon is just starting to brown on the edges while remaining underdone and pliable. Drain bacon on a plate lined with paper towels and, once cool, cut each slice in half. Reduce oven temperature to 350°F.
While bacon cooks, bring a large pot of water to a boil. Blanch green beans by plunging them into the boiling water for 3 minutes. Drain and immediately transfer beans to a large bowl of ice water to stop the cooking process.
In a small pot, melt the butter. Mix in salt, garlic powder, and brown sugar until well blended.
To assemble bundles, lay 8 to 12 beans in a pile (or less, depending on the thickness of your beans). Take a half piece of bacon and wrap it around the top of the green bean bundle, tucking the ends underneath. Lay the bundle on a baking sheet with the bacon seam-side down. Repeat with all green beans.
Using a spoon, evenly drizzle the butter/sugar mixture over each green bean bundle. Season with freshly cracked black pepper, to taste.
Roast at 350°F for 20 to 25 minutes or until bacon is crisp and cooked through. Allow to rest on the baking pan for 3 to 5 minutes before serving.
My green beans were fairly thin (the French haricort vert variety), and 10 per bundle worked out perfectly.
Since a half slice of bacon will not wrap around the green beans more than once, take care that your bundles don't fall apart when you transfer them from the baking sheet. I like to grip each bundle firmly with tongs so that it stays together.
If you prefer, you may brush on the butter/sugar glaze with a pastry brush, as opposed to using a spoon.